Toe stop for roller skates

ABSTRACT

A toe stop has a flat floor-engaging surface disposed at such an angle to a mounting stud that it engages flat against the floor when the skate is tipped forwardly. The portion having the floorengaging surface is molded of relatively soft plastic having a high coefficient of friction, and the portion in which the mounting stud is embedded is formed of relatively hard plastic with a lower coefficient of friction.

United States Patent Heitfield [54] TOE STOP FOR ROLLER SKATES [72]Inventor: Vernon D. Heitfield, Purcellville,

[73] Assignee: William Buffington, Jacksonville,

Fla.

[22] Filed: Sept. 7, 1971 211 App]. No.: 178,312

[52] US. Cl. ..280/l1.2 [51] Int. Cl ..A63c 17/14 [58] Field of Search..280/11.2; 188/251R, 251 A [56] References Cited UNITED STATES PATENTS2,373,698 4/1945 McGeary et a]. ..188/251 A 2,485,147 10/1949 Fowlkes..280/1 1.2

[451 Oct. 24', 1972 Balstead ..280/l 1.2 X

2,631,861 3/1953 Daniska ..280/1 1.2 2,941,812 6/1960 Reynolds ..280/11.2 3,016,246 l/l962 Ware ..280/l1.2

Primary Examiner-Benjamin Hersh Assistant Examiner-D. M. MitchellAttorney-James H. Littlepage 5 7] ABSTRACT A toe stop has a flatfloor-engaging surface disposed at such an angle to a mounting stud thatit engages flat against the floor when the skate is tipped forwardly.The portion having the floor-engaging surface is molded of relativelysoft plastic: having a high coefficient of friction, and the portion inwhich the mounting stud is embedded is formed of relatively hard plasticwith a lower coefficient of friction.

5 Claims, 3 Drawing Figures PATENTED um 24 1912 INVENTOR VERNON D.HEITFIELD ATTORNEY 1 I TOE STOP FOR ROLLER SKATES FIELD OF INVENTIONLand Vehicles, Skates, Wheeled, With brake.

SUMMARY OF INVENTION I-Ieretofore, toe stops shaped generally like theheel of a shoe, as is the present one, have beenmolded of rubber or thelike plastic friction material. Conventionally, these toe stops aremounted by means of a stud in a socket at the front of a skate, the studhaving one end embedded in the friction material. Usually, there is somesort of anchor, such as a washer, on the inner end of the stud.

Such toe stops are used as brakes, and also as traction devices for faststarts. The skate is tipped forwardly until the stop engages the floor,and in starting, considerable forces which tend to twist, tilt ordistort the stop are applied. I-Ieretofore, when conventional rubber orrubber-like plastics were used, such materials with sufficiently highcoefficient of friction for traction could be selected, but these werecharacterized by ten dencies to give, with resultant infirmities infooting.

The object now is to provide a toe stop molded of polyurethane, in whichtwo parts are bonded together during the molding process, one of theparts, i.e., the part which holds the stud, being relatively hard, andthe other part, i.e., the part which engages the floor, being relativelysoft, with a relatively high coefficient of friction.

These and other objects will be apparent from the followingspecification and drawings, in which:

FIG. 1 is a side elevation of the toe stop in typical position on askate;

FIG. 2 is a cross-section through the toe stop; and,

FIG. 3 is a cross-section along theline 33 of FIG. 1.

Referring now to the drawing, the subject toe stop 12 is shown in FIG. Iin its typical use location on the front end of a skate 2, for example,as shown in the US. Pat. to Reynolds, No. 2,941,812, although it isusable on many otherskate mountings. Typically, a roller skate 2 hasrear wheels 4, front wheels 6, a female threaded stud socket 8 extendingdownwardly and forwardly beneath the skate toe plate 10. Usually, thestud socket has some sort of clamp 11 to keep the stud from tuming, onceit is threaded into place.

This invention is concerned with toe stop 12, which is in the generalform of a shoe heel, having a rounded front side 14, flat back side 16,flat bottom '18 and a stud projecting from the top 21. The angle of stud20 with respect to the flat bottom 18 is about 69, so that when theskate is tipped forwardly about front wheels 6 enough to raise rearwheels 4 about one inch off the floor, the flat bottom 18 of the stopengages flat against the floor. Stop 18 is divided into two portions,

an upper portion 22 formed of relatively hard elastomer, and a lowerportion 24 formed of softer elastomer having a higher coefficient offriction than the upper portion. Through a hole through the inner end ofstud 20 engages a cross pin 26 to keep the stud from turning in thematerial of the upper portion 22 in which it is embedded.

The toe stop, save for the stud and cross pin, is molded of two types ofpolyurethane. Stud 20 with its cross-pin up is supported in an open topmold and the elastomer for the upper portion of the stop is poured intothe mold around the stud. The material for this upper portion is duPontsL-3 l5 Urethane, sold under the trademark Adiprene. Its significantcharac-' teristic is that it, like the elastomer for the lower portion,is water-resistant and when cured under standard procedures, it has ahardness of 74 on the Shore D scale. The Adiprene, heated to 212 F andmixed with a suitable cross-linker, such as duPonts Moca, and acatalyst, such as azelaic acid (both the latter heated to about 235 F)is first poured into the mold and allowed to set sufficiently so that itwill not mix appreciably with the material for the bottom part of thestop. Then the material for the bottom part is poured into the mold ontop of the then partly set Aldiprene. The material used for the bottompart is American Cyaninides CA9 Cyanaprene." When set, this has ahardness of on the Shore A scale, and has a considerably highercoefficient of friction than the Adiprene. This, like the Adiprene, ismixed with pigment, heated to 212 F, the cross-linker and catalyst aremixed and heated to about 235 F and poured in on top of the Adiprene.The mold is then moved through a 212 F oven until both the plastics areset. The urethanes, cross linker, pigment and catalyst, mold, oven andmixing procedures are all well known in the urethane art so that furtherspecification is unnecessary.

When the stop is ejected from the mold, stud 20 is firmly embedded inthe hard plastic material of the top, and cannot be unscrewed outwardlybecause of crosspin 26. When the bottom of the stop is pressed againstthe floor, a firm, unyielding engagement is achieved, despite therelative softness of the lower part 24.

I claim:

l. A toe stop for roller skates comprising a solid body having an upperportion bounded on its top side by an upper surface, and a stud embeddedin said upper portion and projecting generally upwardly from said uppersurface, and

a lower portion contiguous to the upper portion and bounded on itsbottom side by a flat surface,

said upper and lower portions being bonded to one another,

said upper portion being formed of relatively hard elastomer material,

said lower portion being formed of relatively soft elastomer materialcharacterized by having a relative high coefficient of friction.

2. A toe stop as claimed in claim 1, said upper and lower portions beingof molded water-resistant polyurethane material, the material of theupper portion being characterized by a hardness of about 74 on the ShoreD scale, the material of the lower portion being characterized by ahardness of about 90 on the Shore A scale.

3. A toe stop as claimed in claim 2, and a cross-pin extending throughthe inner end of said stud for.

preventing rotation thereof in said upper portion.

4. A toe stop as claimed in claim 3, said body having a rounded frontside and a flat rear side, said stud being disposed at an angle to theflat bottom side of said lower portion so that the free end thereofprojects towards the rear of the stop body.

5. A toe stop as claimed in claim 4, the included angle between the studand the flat bottom being about 69.

1. A toe stop for roller skates comprising a solid body having an upperportion bounded on its top side by an upper surface, and a stud embeddedin said upper portion and projecting generally upwardly from said uppersurface, and a lower portion contiguous to the upper portion and boundedon its bottom side by a flat surface, said upper and lower portionsbeing bonded to one another, said upper portion being formed ofrelatively hard elastomer material, said lower portion being formed ofrelatively soft elastomer material characterized by having a relativehigh coefficient of friction.
 2. A toe stop as claimed in claim 1, saidupper and lower portions being of molded water-resistant poly-urethanematerial, the material of the upper portion being characterized by ahardness of about 74 on the Shore D scale, the material of the lowerportion being characterized by a hardness of about 90 on the Shore Ascale.
 3. A toe stop as claimed in claim 2, and a cross-pin extendingthrough the inner end of said stud for preventing rotation thereof insaid upper portion.
 4. A toe stop as claimed in claim 3, said bodyhaving a rounded front side and a flat rear side, said stud beingdisposed at an angle to the flat bottom side of said lower portion sothat the free end thereof projects towards the rear of the stop body. 5.A toe stop as claimed in claim 4, the included angle between the studand the flat bottom being about 69*.